$($a$)$

What is the final velocity, in m$/$s$,$ of a hoop that rolls without slipping down a $8\mathrm{.}40$ m high hill, starting from rest?

m$/$s

$($b$)$

What would be the final velocity, in m$/$s$,$ if a disk of the same mass and radius as the hoop rolled down the hill?

m$/$s